Post navigation

It’s been a wet, cloudy year for George Observatory, but flooding and poor viewing nights at Brazos Bend State Park haven’t kept astronomers from dreaming. Big breakthroughs have happened at the George in the past, and with a complete restoration of the 36-inch, deep space Gueymard Research Telescope, a return to astronomical research is quite simply a waiting game. And with even more rainfall this week, astronomers will have to wait a little longer. The park will remain closed until at least July 12.

“We couldn’t do research forever because of the lens,” George Director Peggy Halford said, referring to the heavy deposits of grime the telescope suffered during its 50 years standing in the muggy climates of Louisiana State University and west Texas wetlands. “And as soon as we got the lens restored, the park flooded.”

Photo posted June 3 on Brazos Bend State Park Facebook page. The post reads, “In the history of the park (since 1984), water levels have never been this high.”

In spite of this development, both amateur and professional astronomers have been using the past 13 months, April and May 2016 in particular, to prioritize future projects using the refreshed equipment. As water over park roads continues to prevent access to the observatory, and cloud cover access to the night sky, these scientists are keeping their heads in the game through planning and pitching sessions.

Photo posted June 2 on Brazos Bend State Park Facebook page. The post reads, “We awoke this morning to find water over Park Road 72 for a roughly 1.25-mile section between Park Headquarters and the Nature Center and a small section between the park entrance and Park Headquarters.”

In an age of computer-guided photometry and NASA probes, the science of star-study from the ground “may not be that glamorous,” Halford offers, but it’s not without significant value. One project idea, for example, involves the study of what happens in space after a supernova goes off, or in science-speak, cataclysmic variable star system follow-up observations.

Not all stars are alone; some come in pairs. Cataclysmic variables are double-star systems that include a super-dense white dwarf and a normal star rapidly orbiting each at a rate of about once an hour. Because the white dwarf is so close to its partner, it strips off material from the normal star’s corona, creating an accretion disk around itself as it accumulates more and more mass..As this energy vacuuming proceeds, unstable matter in the accretion disk occasionally ignites, ejecting a flash of light called a nova. Eventually, the white dwarf will absorb enough of its partner’s energy to detonate a super-massive thermonuclear explosion of incredible power — a supernova. The novae and supernovae of cataclysmic variables are recorded in all cases, but few events are studied, according to Halford.

“The big surveys are great at catching these things in outburst, but there’s little value in the discovery if no follow-up is done,” Halford stated. “The follow-up photometry gives us the rate of fade, and an idea of the characteristics of a particular type of variable, or an idea of the angular momentum of accretion disk in a binary system, et cetera.”

In other words, the moments after novae are some of the most crucial in the effort to know more about these systems, and the lives and behavior of stars in general. Science being an empirical pursuit, the more data, the better. The Gueymard is particularly suited to this type of research given its deep-space capabilities as well as its accessibility to Houston local astronomers.

The relative size of all asteroids visited by spacecraft as of November 2010.

For the purists, the observatory offers an opportunity to discover asteroids — large bodies of rock and ice within our solar system — through classic methods. While computerized telescopes can now scan for inter-planetary bodies and minor planets much faster than a human ground observer, the pursuit is no less exciting or valuable when new discoveries are made.

“In years past, we’ve had astronomer teams that have discovered more than 500 asteroids,” Halford said. “We have a few people who are going to continue to do it by hand and by eye. If they did discover one coming toward Earth, it could potentially be life-saving.”

George astronomers have also proposed a project that could track light pollution in the area using the magnitude of stars. With this set of data, they could fight for more governmental regulation of municipal lighting. Halford and other interested volunteers at the George have already won battles in the fight to keep the skies dark.

Photos of the night sky before and during the Aug. 14, 2003 blackout in the northeast U.S. and Canada. In urban areas, the Milky Way and orbiting satellites suddenly became visible without light pollution.

“About 15 years ago when we heard the Grand Parkway was going to be built, with the museum’s support, we talked to the state legislature and got a bill passed that allowed us to talk to county commissioners about light in unincorporated areas,” Halford said. “There is currently a lighting ordinance around the George Observatory.”

As Houston and surrounding cities continue to grow, studies of how light affects the appearance of the night sky will provide continuing support for the astronomy community and preservation in general. From the star-lover’s perspective, the sky is yet another endangered species or threatened environment.

While the water continues to recede, these astronomers will continue to plan. The McDonald Observatory in west Texas is always an option, but that means a 12-hour drive and it’s expensive to get time on the telescopes, according to Halford.

“We can’t get to our telescope, so now’s the time to throw out some ideas,” she said. “For the local astronomer who wants to contribute to the scientific body of knowledge, this is the best place to do it.”

April 25 will mark the 25th anniversary of the world-famous Hubble Space Telescope, and the George Observatory will celebrate with a debut of their restored 36-inch Gueymard Research Telescope, the largest specialized Cassegrain telescope open to the public, and the only one that chooses to use an eyepiece.

The Gueymard Research Telescope, a 36-inch Ritchey—Chretien Cassegrain.

“You can see the images with your own eyes instead of on a computer screen like other telescopes,” George Observatory Director Peggy Halford said. “It gives you a much more personal experience.”

A Ritchey—Chretien design, the telescope features hyperbolic primary and secondary mirrors which sharpen the image, eliminating the fuzzy edges around its center, what is known to astronomers as an off-axis coma. With optics this precise, the telescope brings to the naked eye the phenomena of deep space.

A couple of years ago, astronomers at the George began to notice the quality of images in the Gueymard was degrading. Views were clearer in the smaller, though still research-grade, 11-inch refractor attached to the Gueymard. While they knew something was wrong, they didn’t expect the adventure they would embark upon to restore it to its original power.

Amateur astronomers remove the primary mirror from the Gueymard Research Telescope.

When they removed the primary mirror, the equivalent of “checking under the hood,” they found environmental pollutants built up in microscopic divots and fissures left on its surface after its original grind 50 years ago. Optical technology has come a long way since then; imperfections in contemporary optics are virtually absent, Halford said. The George acquired the telescope from Louisiana State University, where it had stood in swamp-like conditions another 25 years prior to its installation in Brazos Bend State Park. Time and humidity had taken its toll.

The Museum sent the delicate 500-pound mirror to a coating company that did the simple things first — a bath and a new reflective coating — to try to refurbish the mirror, but the coating refused to stick, and they knew they would need to bring in the big guns.

The wooden container the George employees used to ship the hyperbolic mirror.

It took a three-month fundraising campaign, Save Our Scope, to raise the money to hire Master Optician James Mulherin to resurface the element. Halford is proud to report the campaign took much less time than she anticipated, given the surprising amount of support from the public.

February 2014, the George again sent mirror away, this time to Mulherin, and a year an a month later, the project was complete. Mulherin took a trip to the George to help install the element, and he sat down to explain the particulars of the resurfacing project and what he does at his business, Optical Mechanics, Incorporated.

One of two specialists in the nation who do this kind of work, Mulherin came highly recommended from amateur astronomers who dropped his name to Halford at star parties when they learned of the George’s difficulty with the Gueymard. What was tough for the astronomers was a piece of cake for Mulherin.

“It was a fairly routine job,” said Mulherin, whom universities and aerospace companies regularly hire for their optical needs. “There was no real challenge.”

Mulherin did mention, however, that he had to work around the hole in the middle of the mirror, where a steel hub goes through to hold the mirror in place at the bottom of the telescope. Normally a glass plug is installed during the grinding phase, but there was too much difference in the composition of this 50-year-old glass and that of contemporary optics, he said, so he had to work around it.

Using specialized equipment to move the delicate, but massive, hunk of glass, Mulherin’s company stripped the aluminum finish and ground down the old surface to remove the imperfections in the element. The opticians then re-shaped the mirror’s hyperbolic curvature, shining light through the glass at different stages to check their progress. Finally, Mulherin coated the surface with enhanced aluminum to increase reflectivity.

The George will debut the repaired Gueymard April 25, coinciding with the 25th anniversary of the Hubble Space Telescope.

The result was a total restoration of the optics, but volunteers still had to put the mirror back into place. The replacement, including the removal of the cement blank used to counterbalance the telescope while the mirror was out, along with cleaning the housing, took Tracy Knauss, Dana Lambert and Chris Randall 10 days straight, working from noon to 10 p.m.

Changes to the width of the mirror required volunteers to adjust the secondary mirrors after the installation of the main element — no small task. Installation and adjustments of the precision optics continued from 8 a.m. to 10 p.m. Monday, and again Tuesday from noon to 10 p.m.

“I wanted to stick an eyepiece into it and it work,” Halford said, but collimating the telescope, or aligning the elements with accuracy, required much more time.

Mulherin said he felt at home at the George during the course of the project, and happy to help.

“I feel like I’m part of the community,” he said. “When I started, we were all amateur astronomers, and I found I was more interested in optics than astronomy.”

About the telescope, he said, “It’s amazing to me that it still works.”

Halford hopes for clear skies April 25, but if conditions turn cloudy, she said, “We’ll just show it off.” The George will observe regular Saturday hours from 3 to 10 p.m. for the event.

First Light & 25th Anniversary of the Hubble Space Telescope CelebrationSaturday, April 253:00 p.m. – 10:00 p.m.April 25 will mark the 25th anniversary of the world-famous Hubble Space Telescope, and the George Observatory will celebrate with a debut of their restored 36-inch Gueymard Research Telescope, the largest specialized Cassegrain telescope open to the public, and the only one that chooses to use an eyepiece.

Of the many meteor showers that occur throughout the year, the Geminid Meteor Shower in December may be the most reliably active. This meteor shower occurs when the Earth passes near 3200 Phaethon, a Palladian Asteroid. The Geminids were first observed in 1862. The shower gets its name because they appear to originate in the Gemini constellation.

Under ideal conditions, one may see as many as 50-100 meteors an hour. The meteors from this shower are also especially bright, and many astronomers believe that the shower is intensifying every year. The shower should peak around 9:00 p.m. on Saturday December 13th. That’s good news because most of the other significant showers, like the Perseids, peak after midnight. With no Moon until after midnight, we should be able to see a lot of meteors (weather permitting of course).

The George Observatory will be open Saturday, December 13th until midnight for viewing the shower. Tickets for viewing the shower are $5 and include access to our telescopes. That night, we’ll be able to view several star clusters and nebulae with our scopes. Jupiter should rise in time to be viewed as well. We’ll also have our Discovery Dome available for $3.

If you can’t make it out to the George, you can still view the shower anywhere with dark skies.

If you follow astronomy websites, you’ve probably noticed that every month or so there’s an article about a meteor shower happening. There are meteors showers frequently throughout the year. Some showers are more active than others depending on various factors. This August one of the most reliably active showers, the Perseids, will take place.

The Perseids, sometimes called The Tears of St. Lawrence, occur when the Earth passes through a debris field created by comet 109P Swift-Tuttle. This year, the meteor shower peaks Tuesday night (August 12) through early Wednesday morning. Besides being one of the most active showers (in 2013 it averaged 109 meteors an hour), the Perseids also have a very broad peak. Meteors can be seen as early as July in some circumstances.

The early meteors which are the first ones to hit the earth’s atmosphere, tend to be the brightest ones with the longest tails.These are called “Earth-grazers” and those are the ones we will be looking for the evening of August 12-13 here at the George Observatory.

This year, the shower will be taking place during another “Supermoon,” occurring August 10. While not at its closest point, this means the Moon will still be very close and bright on August 12. Normally, this would not be an ideal night for observing meteors since the Moon will flood the sky with light.

Our astronomers like to joke that “Moon” is a four letter word.

But don’t fret! The Moon won’t rise until 9:30 p.m. that night and, with our high tree-line here at the George Observatory, it won’t start affecting viewing until at least 10 p.m. Also, even after the Moon rises, the brightest meteors will still shine through.

In 2011, the Perseids peaked on a full Moon and people still saw an average of over 50 meteors an hour. This year the Moon will be a waxing gibbous (progressing from the full moon to the new moon).